• Nick (11/11) Aug 01 2004 While the complex number support of D is great, I've noticed that phobos...
• parabolis (3/9) Aug 01 2004 I think somebody is currently working on math related functions.
• Nick (6/11) Aug 01 2004 A long double has two unused bytes, and a complex is composed of two of ...
• Walter (8/19) Aug 01 2004 Are you working with gcc?
• Nick (4/5) Aug 01 2004 Nah, why'd you think that? :) I've just done some experimenting with com...
• Walter (5/11) Aug 01 2004 complex

Nick <Nick_member pathlink.com> writes:

While the complex number support of D is great, I've noticed that phobos still
lacks most math functions for complex numbers. In the mean time I thought I'd
try importing some functions from C, but haven't had much luck with this.

Since you can import non-complex math functions by using the 'real' type
directly, I thought you also might be able to do something like

extern (C) creal cexpl(creal);

but calling this just gives a segfault :( I've also tried calling the functions
with 24 byte structs (a gcc complex long double is 24 bytes, not 20 like creal)
but it still gives the occational segfault (I think it's messing up the stack.)

Anybody who can help me?

Nick

parabolis <parabolis softhome.net> writes:

Nick wrote:

 but calling this just gives a segfault :( I've also tried calling the functions
 with 24 byte structs (a gcc complex long double is 24 bytes, not 20 like creal)
 but it still gives the occational segfault (I think it's messing up the stack.)

What do they do with the extra 4 bytes?

 
 Anybody who can help me?
 

I think somebody is currently working on math related functions.

Nick <Nick_member pathlink.com> writes:

In article <cej9ja$28nr$1 digitaldaemon.com>, parabolis says...
Nick wrote:

 but calling this just gives a segfault :( I've also tried calling the functions
 with 24 byte structs (a gcc complex long double is 24 bytes, not 20 like creal)
 but it still gives the occational segfault (I think it's messing up the stack.)

What do they do with the extra 4 bytes?

A long double has two unused bytes, and a complex is composed of two of those.
The two bytes take on semi-random values depending on which function created
them and are ignored in any calculation. The 80 bit float is the maximum on
Intel processors, so I guess they are reserved for other architectures.

Nick

"Walter" <newshound digitalmars.com> writes:

Are you working with gcc?

"Nick" <Nick_member pathlink.com> wrote in message
news:cej7jg$285p$1 digitaldaemon.com...
 While the complex number support of D is great, I've noticed that phobos

still
 lacks most math functions for complex numbers. In the mean time I thought

I'd
 try importing some functions from C, but haven't had much luck with this.

 Since you can import non-complex math functions by using the 'real' type
 directly, I thought you also might be able to do something like

 extern (C) creal cexpl(creal);

 but calling this just gives a segfault :( I've also tried calling the

functions
 with 24 byte structs (a gcc complex long double is 24 bytes, not 20 like

creal)
 but it still gives the occational segfault (I think it's messing up the

stack.)
 Anybody who can help me?

 Nick

Nick <Nick_member pathlink.com> writes:

In article <cejibv$2c39$2 digitaldaemon.com>, Walter says...
Are you working with gcc?

Nah, why'd you think that? :) I've just done some experimenting with complex
numbers in C using gcc.

Nick

"Walter" <newshound digitalmars.com> writes:

"Nick" <Nick_member pathlink.com> wrote in message
news:cejqit$2erh$1 digitaldaemon.com...
 In article <cejibv$2c39$2 digitaldaemon.com>, Walter says...
Are you working with gcc?

 Nah, why'd you think that? :) I've just done some experimenting with

complex
 numbers in C using gcc.

I suspect the problem is in the function return conventions used by the
compiler. It's easy enough to check.